MBM29SL160BD Просмотр технического описания (PDF) - Fujitsu

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MBM29SL160BD

FLASH MEMORY CMOS 16M (2M × 8/1M × 16) BIT

Fujitsu 

MBM29SL160TD-10/-12/MBM29SL160BD-10/-12

Write

Device erasure and programming are accomplished via the command register. The contents of the register serve

as inputs to the internal state machine. The state machine outputs dictate the function of the device.

The command register itself does not occupy any addressable memory location. The register is a latch used to

store the commands, along with the address and data information needed to execute the command. The

command register is written by bringing WE to VIL, while CE is at VIL and OE is at VIH. Addresses are latched on

the falling edge of WE or CE, whichever happens later; while data is latched on the rising edge of WE or CE,

whichever happens first. Standard microprocessor write timings are used.

Refer to AC Write Characteristics and the Erase/Programming Waveforms for specific timing parameters.

Sector Group Protection

The MBM29SL160TD/BD feature hardware sector group protection. This feature will disable both program and

erase operations in any combination of seventeen sector groups of memory. (See Tables 2.1 and 2.2). The sector

group protection feature is enabled using programming equipment at the user’s site. The device is shipped with

all sector groups unprotected.

To activate this mode, the programming equipment must force VID on address pin A9 and control pin OE, (suggest

VID = 10V to 11V), CE = VIL and A0 = A6 = VIL, A1 = VIH. The sector group addresses (A19, A18, A17, A16, A15, A14,

A13, and A12) should be set to the sector to be protected. Tables 1.1 and 1.2 define the sector address for each

of the thirty nine (39) individual sectors, and tables 2.1 and 2.2 define the sector group address for each of the

seventeen (17) individual group sectors. Programming of the protection circuitry begins on the falling edge of

the WE pulse and is terminated with the rising edge of the same. Sector group addresses must be held constant

during the WE pulse. See figures 16 and 25 for sector group protection waveforms and algorithm.

To verify programming of the protection circuitry, the programming equipment must force VID on address pin A9

with CE and OE at VIL and WE at VIH. Scanning the sector group addresses (A19, A18, A17, A16, A15, A14, A13, and

A12) while (A6, A1, A0) = (0, 1, 0) will produce a logical “1” code at device output DQ0 for a protected sector.

Otherwise the device will produce “0” for unprotected sector. In this mode, the lower order addresses, except

for A0, A1, and A6 are DON’T CARES. Address locations with A1 = VIL are reserved for Autoselect manufacturer

and device codes. A-1 requires to apply to VIL on byte mode.

It is also possible to determine if a sector group is protected in the system by writing an Autoselect command.

Performing a read operation at the address location XX02H, where the higher order addresses (A19, A18, A17,

A16, A15, A14, A13, and A12) are the desired sector group address will produce a logical “1” at DQ0 for a protected

sector group. See Tables 6.1 and 6.2 for Autoselect codes.

Temporary Sector Group Unprotection

This feature allows temporary unprotection of previously protected sector groups of the MBM29SL160TD/BD

devices in order to change data. The Sector Group Unprotection mode is activated by setting the RESET pin to

high voltage (VID). During this mode, formerly protected sector groups can be programmed or erased by selecting

the sector group addresses. Once the VID is taken away from the RESET pin, all the previously protected sector

groups will be protected again. Refer to Figures 17 and 26.

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